New study suggests dogs cry tears of happiness when reunited with their owners

Basset Hound lying on floor with tears in eyes
(Image credit: Getty Images)

If you’ve ever thought your pup’s eyes look a little moist whenever they’re reunited with you, you may just be onto something with a new study suggesting that dogs cry tears of happiness when their owners come home. 

The research, conducted by a group of scientists at the Laboratory of Human-Animal Interaction and Reciprocity at Azabu University in Japan, was launched after professor Takefumi Kikusui noticed that one of his poodles became tearful while nursing her new puppies.

It got Kikusui thinking about whether dogs experience emotions in much the same way that humans do. To investigate whether such a link existed, Kikusui and his team measured the amount of tears among 18 dogs, placing a paper strip inside the eyelids of each dog for a minute before and after they were reunited with their human.

Sure enough, the researchers found that the amount of moisture collected on the paper strip increased in the moments following the dogs' reunion with their owners, leading them to conclude that being back together with their human stimulated tear secretion

"We found that dogs shed tears associated with positive emotions," Kikusui explains. We also made the discovery of oxytocin as a possible mechanism underlying it."

To ensure the results were accurate, Kikusui also tried separating the dogs from their owners and instead reuniting them with another known caretaker but found that there was “no increase in tears when the dogs were separated from the owner and reunited with the dogs’ caretaker in a dog care center,” suggesting that the emotional response was specific to their owner.

So, next time you come home and your canine companion excitedly greets you at the door, be sure to give them an extra big hug because it turns out they feel your absence more than you know. 

Kathryn Williams
Freelance writer

Kathryn is a freelance writer who has been a member of the PetsRadar family since it launched in 2020. Highly experienced in her field, she's driven by a desire to provide pet parents with accurate, timely, and informative content that enables them to provide their fur friends with everything they need to thrive. Kathryn works closely with vets and trainers to ensure all articles offer the most up-to-date information across a range of pet-related fields, from insights into health and behavior issues to tips on products and training. When she’s not busy crafting the perfect sentence for her features, buying guides and news pieces, she can be found hanging out with her family (which includes one super sassy cat), drinking copious amounts of Jasmine tea and reading all the books.